Sawmill



p .1967 M. L. SUMMERLAND 3,340,910

SAWMILL F iled Oct. 25, 1965 MAM-M701? M54 WM 1.. SOMM5/PA4A/0 United States Patent Ofifice 3,340,910! Patented Sept. 12, 1967 This invention relates generally to sawmills, and more particularly to sawmills having multiple disc saws.

In the cutting of semi-rough lumber into smaller strips or planks, it is desirable to improve efiiciency by increasing the speed and accuracy of the saw cuts. Accordingly, it is an object of this invention to provide a sawmill with multiple disc saws for making several simultaneous cuts in a piece of rough timber.

It is a further object of this invention to provide a sawmill having multiple disc saws with an improved means for controlling the accuracy of simultaneously made cuts.

Other objects, advantages and novel features of this invention will become apparent from the following specification, of which the accompanying drawings form a part.

In these drawings:

FIG. 1 is a partially fragmented plan view of the sawmill of this invention;

FIG. 2 is a partially fragmented side elevational View of the sawmill of FIG. 1;

FIG. 3 is an end view of the table and carriage portion of the sawmill;

FIG. 4 is a cross-sectional view of the guide bar taken along line 44 of FIG. 1, and showing a portion of a pressure finger and saw blade.

Referring now to the drawings, the sawmill of this invention generally comprises a saw assembly 10, a frame 12, and a table assembly 14.

Saw assembly comprises a plurality of circular disc saws 16 mounted upon a single arbor 18. The spacing and number of adjacent saws 16 is controlled by spacing collars 20 which may be mounted at any point along arbor 18. Arbor 18 is driven by motor 22 and chain or belt drive 24. Saw assembly 10 is supported on a pair of horizontal frame members 26 which in turn are mounted on a pair of upright frame members 28. Frame members 28 are pro- 1 vided with slots or multiple holes (not illustrated) to permit adjustment of the height of the disc saws.

Parallel and horizontal front and rear rollers 30 and 32, respectfully, are mounted upon frame 12 at equal elevations. Also mounted to frame 12, at a point intermediate arbor 18 and front roller 30, is a guide bar 34.

A number of pressure fingers 36 are slidably mounted over L-shaped tongue 38 of guide bar 34. Notch 40 in the guide bar provides a space for pressure fingers 36 to be added to or subtracted from the guide bar after guide bar 34 is assembled to the frame. As can be seen from FIG. 1, the pressure fingers 36 are intermeshed with saws 16. Spacing elements (not illustrated) between the slotted ends of the pressure fingers establish the desired spacing.

Means may be provided (not illustrated) for varying the heights of rollers 30 and 32 and bar 34. The function of these elements will be described below.

The piece of wood to be processed by the sawmill, known as a cant, is illustrated at 42 in the drawings. A cant is a portion of a log which has been rough cut on three sides. Cant 42 is supported on table 44 which is in turn mounted upon carriage 46. Carriage 46 is provided with four wheels 48 which ride in parallel channel shaped tracks 50, best seen in FIG. 3. A channel shaped side guide 52 fixed to frame 12. provides a fixed lateral locating means against which cant or workpiece 42 abuts during its progress through the saws.

Table 44 is resiliently mounted to carriage 46 on springs 54, which can be seen in FIG. 3. Relative movement between the table and the carriage is constrained to lie purely in a vertical direction by means of side stops 56, which prevent lateral displacement of the table, and by transverse channels 58, which lie within grooves in the underside of table 44 and prevent longitudinal movement of the table relative to the carriage.

The table may be fed through the saws by hand or by power means (not illustrated). To transmit the feeding force from the carriage and table to the cant, lugs 60 are provided in the top surface of table 44.

Slots 62 are cut in the top surface of table 44 to provide passage for the saws 16 as they cut completely through the cant.

Operation As cant 42 is fed by table 44 and carriage 46 toward the saws, the leading upper edge of the cant first encounters roller 30. The bottom edge of roller 30 is set at a height off the top surface of the table less than the thickness of the cant. The cant and table are therefore cammed downwardly with respect to carriage 46 against the resistance of springs 54. This initial compression of springs 54 securely clamps the cant or workpiece to the table. As the table progresses toward the saws, the front upper edge of the cant contacts the beveled under face of guide bar 34 and pressure fingers 36 are set an elevation slightly lower than that of the lowermost surface of front roller 30. The cant and table are therefore cammed downwardly still further as the cant encounters guide bar 34, thus further compressing springs 54 and securing the cant to the table with still greater force.

Since pressure fingers 36 extend well into the spaces between the disc saws 16, the cant 34 remains securely clamped to the table throughout its passage through the saws. Rear roller 32 assists the pressure fingers in maintaining this clamping pressure after the cant has begun to leave the saw zone.

Without the provision of pressure fingers 36 extending all the way into the space between the saws, the upward motion of the left hand portion of the saws (as viewed in FIG. 2) would tend to lift the cant off the table surface. This would result in slippage or relative movement between the cant and the table and would simultaneously reduce the accuracy of the cuts.

Thus, the efficiency of the sawmill has been greatly improved by making a plurality of simultaneous cuts during a single pass and by providing means for securely and firmly clamping the workpiece to the table throughout its passage through the saws.

This invention may be further developed within the scope of the following claims. The above specification is descriptive of only a single operative embodiment of the invention and is not to be interpreted in a strictly limited sense.

I now claim:

1. A sawmill comprising:

a supporting frame including a pair of parallel horizontal guide tracks running from a first to a second end of said frame;

a carriage having a plurality of wheels rotatably mounted thereon, said wheels so disposed as to ride on said guide tracks;

feed means for causing said carriage to travel between said first and second ends of said frame;

a table disposed directly above and resiliently sup ported on said carriage;

a horizontal arbor having a plurality of disc saws fixed at spaced interval-s thereto, said arbor being mounted on said frame above said table and transverse to said guide tracks;

drive means for rotatably driving said arbor;

first and second horizontal rollers parallel to said arbo and spaced on opposite sides thereof;

said first and second rollers being secured to said frame and equally spaced above said table a distance only slightly less than the height of said arbor above said table;

a guide bar parallel to said arbor and fixed to said frame intermediate said arbor and said first roller, said guide bar having a plurality of spaced horizontal pressure fingers mounted thereon, said pressure fingers being parallel to said guide tracks and extending into the spaces between said disc saws, the lower edge of said guide bar and said fingers being slightly below the level of the lower most edge of said first and second rollers;

the height of said guide bar and pressure fingers above the normal height of said table, being set to a dimension less than the height of a workpiece to be processed by the sawmill;

whereby as a workpiece placed on said table is fed towards said disc saws by said feed means, it is cammed downwardly by said first roller, said guide bar, said pressure plate, and said second roller, thereby to securely clamp the workpiece to said table as it passes through said saws.

2. A sawmill comprising:

a supporting frame;

a carriage mounted for horizontal reciprocal movement along said frame;

a table disposed directly above and resiliently supported on said carriage for vertical displacement relative thereto;

a horizontal arbor having a plurality of disc saws fixed at spaced intervals thereto, said arbor being mounted on said frame above said table and transverse to the reciprocal path of said carriage;

drive means for rotatably driving said arbor;

a guide bar parallel to said arbor fixed to said frame, said guide bar being horizontally displaced from said arbor;

said guide bar having a plurality of spaced horizontal pressure fingers mounted thereon, said pressure fingers extending perpendicularly from said guide bar into the spaces between disc saws;

the lowermost surface of said guide bar and said pressure fingers being spaced above the normal height of said table a distance less than the thickness of a workpiece to be processed by the sawmill;

whereby as a workpiece is fed on said table toward and through said disc saws, it and the supporting table are cammed downwardly by said guide bar and said pressure fingers, thereby securely clamping the workpiece to said table during the sawing operation.

3. The sawmill of claim 2, which further comprises:

a horizontal roller parallel to said arbor and mounted to said frame on the opposite side of said arbor from said guide bar, the height of said roller above said table being substantially equal to that of said guide bar;

whereby said roller maintains downward clamping pressure on the workpiece after it passes out from beneath said pressure fingers.

4. A sawmill comprising:

a supporting frame including a *pair of parallel horizontal guide tracks running from a first to a second end of said frame;

a carriage slidably mounted upon said guide tracks;

feed means for causing said carriage to slidably travel between said first and second ends of said frame;

a table disposed directly above and resiliently supported on said carriage for upwards vertical movement relative to said carriage;

a horizontal arbor having a plurality of disc saws fixed at spaced intervals thereto, said arbor being mounted on said frame above said table and transverse to said guide tracks;

drive means for rotatably driving said arbor;

first and second horizontal rollers parallel to said arbor and spaced on opposite sides thereof above the plane of said table;

said first and second rollers being secured to said frame and equally spaced above said table a distance only slightly less than the height of said arbor above said table;

whereby as a workpiece placed on said table is fed towards said disc saws by said feed means, it is pressure held downwardly by the opposition force of said first roller and said second roller opposing the upwards pressure of the resilient support of said table, thereby to securely clamp the workpiece to said table as it passes through said saws.

References Cited UNITED STATES PATENTS 201,198 3/1878 Randolph 143 37 2,305,170 12/1942 Jackson 143 2,673,581 3/1954 Dornathetal 143 37x 3,245,440 4/1966 Baumletal 143 52 3,275,045 9/1966 Beely 143 37 WILLIAM W. DYER, JR., Primary Examiner.

W. D. BRAY, Assistant Examiner. 

1. A SAWMILL COMPRISING: A SUPPORT FRAME INCLUDING A PAIR OF PARALLEL HORIZONTAL GUIDE TRACKS RUNNING FROM A FIRST TO A SECOND END OF SAID FRAME; A CARRIAGE HAVING A PLURALITY OF WHEELS ROTATABLY MOUNTED THEREON, SAID WHEELS SO DISPOSED AS TO RIDE ON SAID GUIDE TRACKS; FEED MEANS FOR CAUSING SAID CARRIAGE TO TRAVEL BETWEEN SAID FIRST AND SECOND ENDS OF SAID FRAME; A TABLE DISPOSED DIRECTLY ABOVE AND RESILIENTLY SUPPORTED ON SAID CARRIAGE; A HORIZONTAL ABSORBER HAVING A PLURALITY OF DISC SAWS FIXED AT SPACED INTERVALS THERETO, SAID ARBOR BEING MOUNTED ON SAID FRAME ABOVE SAID TABLE AND TRANSVESE TO SAID GUIDE TRACKS; DRIVE MEANS FOR ROTATABLY DRIVING SAID ARBOR; FIRST AND SECOND HORIZONTAL ROLLERS PARALLEL TO SAID ARBOR; AND SPACED ON OPPOSITE SIDES THEREOF; SAID FIRST AND SECOND ROLLERS BEING SECURED TO SAID FRAME AND EQUALLY SPACED ABOVE SAID TABLE A DISTANCE ONLY SLIGHTLY LESS THAN THE HEIGHT OF SAID ARBOR ABOVE SAID TABLE; A GUIDE BAR PARALLEL TO SAID ARBOR AND FIXED TO SAID FRAME INTERMEDIATE SAID ARBOR AND SAID FIRST ROLLER, SAID GUIDE BAR HAVING A PLURALITY OF SPACED HORIZONTAL PRESSURE FINGERS MOUNTED THEREON, SAID PRESSURE FINGERS BEING PARALLEL TO SAID GUIDE TRACKS AND EXTENDING INTO THE SPACES BETWEEN SAID DISC SAWS, THE LOWER EDGE OF SAID GUIDE BAR AND SAID FINGERS BEING SLIGHTLY BELOW THE LEVEL OF THE LOWER MOST EDGE OF SAID FIRST AND SECOND ROLLERS THE HEIGHT OF SAID GUIDE BAR AND PRESSURE FINGERS ABOVE THE NORMAL HEIGHT OF SAID TABLE, BEING SET TO A DIMENSION LESS THAN THE HEIGHT OF A WORKPIECE TO BE PROCESSED BY THE SAWMILL; WHEREBY AS A WORKPIECE PLACED ON SAID TABLE IS FED TOWARDS SAID DISC SAWS BY SAID FED MEANS, IT IS CAMMED DOWNWARDLY BY SAID FIRST ROLLER, SAID GUIDE BAR, SAID PRESSURE PLATE, AND SAID SECOND ROLLER, THEREBY TO SECURELY CLAMP THE WORKPIECE TO SAID TABLE AS IT PASSES THROUGH SAID SAWS. 